Tianling Li Luji Bo Fan Yang Shanqing Zhang Yonghong Wu Linzhang Yang. Comparison of the removal of COD by a hybrid bioreactor at low and room temperature and the associated microbial characteristics. Bioresource Technology 2012 108: 28–34.

Abstract

To improve the efficiency of wastewater treatment and characterize the microorganism communities microorganisms were cultured and concentrated in hybrid bioreactors at a low temperature (4 C low-temperature hybrid bioreactor LTHB) and room temperature (25 C room-temperature hybrid bioreactor RTHB). The performance of the LTHB and RTHB in terms of COD removal efficiency dehydrogenase activity and functional diversity of microbial communities were evaluated. The results show COD removal efficiency increased gradually over time from 39.76% to 66.27% for LTHB and fluctuated between 81.85% and 94.78% for RTHB. The dehydrogenase activity and microbial activity in LTHB was higher than those in RTHB implying that microorganisms cultured at low temperature had higher activities and adaptabilities than those cultured at room temperature. This study suggests that hybrid bioreactors can treat wastewater at both low and room temperatures and provides valuable insight into the adaptation processes of the microorganisms during temperature changes.

Xuanzhen Li Yucheng Wu Xiangui Lin Jing Zhang Jun Zeng. Dissipation of polycyclic aromatic hydrocarbons (PAHs) in soil microcosms amended with mushroom cultivation substrate. Soil Biology & Biochemistry 2012 47: 191-197.

Abstract

The potential of mushroom cultivation substrate (MCS) in bioremediation was examined in polycyclic aromatic hydrocarbon (PAH)-contaminated soil. After a 60-day incubation 32.9% dissipation of the 15 studied PAHs was observed in MCS-amended microcosms with anthracene benzo(a)pyrene and benzo(a)anthracene being the most degradable PAHs. MCS significantly increased the abundance and changed the community compositions of bacteria fungi and aromatic hydrocarbon degraders. Two species belonging to the Sordariomycetes of the Ascomycota were enriched in all MCS-treated soil samples and coupled with the unique changes in the PAH profile this implies the involvement of laccase-like enzymes. Limited improvement was observed after adding Pleurotus ostreatus possibly  because of its poor colonization of the soil. In addition alfalfa appeared to antagonize the bioremediation effects of MCS. The results of this study suggest that MCS can be a cost-effective and green biostimulation agent thereby providing support for the development of MCS-based biostimulation of PAH-contaminated soil.

Hongyan Guo Ran Tian Jianguo Zhu Hui Zhou Daping Pei Xiaorong Wang. Combined cadmium and elevated ozone affect concentrations of cadmium and antioxidant systems in wheat under fully open-air conditions. Journal of Hazardous Materials 2012 209– 210: 27– 33.

Abstract

Pollution of the environment with both ozone (O3) and heavy metals has been steadily increasing. An understanding of their combined effects on plants especially crops is limited. Here we studied the effects of elevated O3 on oxidative stress and bioaccumulation of cadmium (Cd) in wheat under Cd stress using a free-air concentration enrichment (FACE) system. In this field experiment in Jiangdu (Jiangsu Province China) wheat plants were grown in pots containing soil with various concentrations of cadmium (0 2 and 10 mg kg−1 Cd was added to the soil) under ambient conditions and under elevated O3 levels (50% higher than the ambient O3). Present results showed that elevated O3 led to higher concentrations of Cd in wheat tissues (shoots husk and grains) with respect to contaminated soil. Combined exposure to Cd and elevated O3 levels strongly affected the antioxidant isoenzymes POD APX and CAT and accelerated oxidative stress in wheat leaves. Our results suggest that elevated O3 levels cause a reduction in food quality and safety.

Deyan Liu Weixin Ding Zhongjun Jia Zucong Cai. The impact of dissolved organic carbon on the spatial variability of methanogenic archaea communities in natural wetland ecosystems across China. Appl Microbiol Biotechnol 2012 96:253–263.

Abstract

Significant spatial variation in CH4 emissions is a well-established feature of natural wetland ecosystems. To understand the key factors affecting CH4 production the variation in community structure of methanogenic archaea in relation to substrate and external environmental influences
was investigated in selected wetlands across China using denaturing gradient gel electrophoresis. Case study areas were the subtropical Poyang wetland the warmtemperate Hongze wetland the cold-temperate Sanjiang marshes and the alpine Ruoergai peatland on the Qinghai–Tibetan Plateau. The topsoil layer in the Hongze wetland exhibited the highest population of methanogens; the lowest was found in the Poyang wetland. Maximum CH4 production occurred in the topsoil layer of the Sanjiang Carex lasiocarpa marsh the minimum was observed in the Ruoergai peatland. CH4 production potential was significantly correlated with the dissolved organic carbon (DOC) concentration but not with the abundance or diversity indices of methanogenic archaea. Phylogenetic analysis and DOC concentration indicated a shift in the dominant methanogen from the hydrogenotrophic Methanobacteriales in DOCrich wetlands to Methanosarcinaceae with a low affinity in wetlands with relatively high DOC and then to the acetotrophic methanogen Methanosaetaceae with a high affinity in wetlands with low DOC or with high DOC but rich sulfate-reducing bacteria. Therefore it is proposed that the dominant methanogen type in wetlands is primarily influenced by available DOC concentration. In turn the variation in CH4 production potential in the wetlands of eastern China is attributable to differences in the DOC content and the dominant type of methanogen present.

    2011年12月29-30日，一年一度的土壤与农业可持续发展国家重点实验室学术年会在南京土壤研究所惠联大楼大礼堂召开。

    南京土壤研究所所长、实验室主任沈仁芳研究员致开幕辞。他简要介绍了实验室一年来的工作进展与实验室人员、研究方向上的调整，并公布了实验室2011年度优秀论文获奖名单。

    两天的会议中共有24名研究员和青年骨干代表对各自课题组取得的重要研究进展作了学术报告。

    在土壤生产力提升与水肥高效利用方面，赵炳梓研究员作了题为“封丘县土壤质量变化及其与作物产量之间关系”学术报告；彭新华研究员报告题为“红壤低丘岗地地区典型农田小流域生态水文过程–初步研究”；姚荣江博士介绍了滨海滩涂土壤水盐运动模拟与控盐灌溉条件下作物水氮利用效率研究进展。

    在农田生态系统碳循环与增汇减排方面，刘钢研究员详细探讨了静态箱采样法中的相关问题，唐昊冶作了“近地层臭氧浓度升高导致的产量损失”学术报告；张广斌博士介绍了稳定性碳同位素自然丰度法在稻田甲烷研究中的应用。

    在农田生态系统氮、磷循环与环境效应方面，颜晓元研究员详细介绍了温室气体排放估算空间尺度扩展方法；尹斌研究员阐述了高产高效措施下的水稻产量与氮素行为特征；吴永红副研究员针对自然生物膜控制农田营养盐流失及其相关污染的机制作了详细阐述。

    在土壤资源演变与数字化管理方面，于东升副研究员作了“LAI表征植被防侵蚀机理及其定量评价”报告；杨金玲副研究员介绍了亚热带地区元素地球化学循环及其对土壤风化和酸化的影响。

    在土壤生物系统功能与调控方面，李忠佩研究员着重介绍了肥际微域氮磷转化及调控措施；孙波研究员作了“秸秆分解过程中有机物和微生物组成结构的协同演变：基于东部温度梯度带的土壤置换试验研究”报告；褚海燕研究员针对高寒生态系统微生物生物地理分布作了学术报告；贾仲君研究员阐述了土壤硝化微生物生理生态过程的分子调控机制；陈瑞蕊博士详细介绍了土壤碳氮转化微生物群落演替与功能变化。

    在土壤-植物互作与绿色施肥方面，段增强研究员报告题为“是根温惹的祸？”；杜昌文研究员介绍了水基聚合物包膜肥料的研制及应用；王火焰研究员介绍了植物高效利用矿物非交换态钾的机制研究；苏彦华研究员介绍了水稻铵吸收运输的分子机理研究；梁林州博士详细介绍了菜园土壤磷素养分管理。

    在土壤界面化学过程与生物效应方面，徐仁扣研究员作了题为“不同温度下制备的秸秆生物质炭中碱的存在形态”学术报告；姜军副研究员介绍了可变电荷土壤发育过程中表面电化学性质的演变特征；杨兴伦副研究员介绍了土壤中有机污染物生物有效性表征研究进展。

    会议报告精彩纷呈，会议现场气氛热烈，尤其是报告后的提问讨论环节，学术思想火花不断碰撞，与会人员都受益颇丰。实验室常务副主任张甘霖研究员对会议作了总结，认为这些报告很好地体现了实验室一年来的研究成果，充分肯定了这次年会的意义，并感谢大家对实验室工作的支持。最后，南京土壤研究所所长、实验室主任沈仁芳研究员为优秀论文获得者颁发了证书与奖励。实验室2011年度学术年会圆满落幕。

Yuchun Ma Jinyang Wang Wei Zhou Xiaoyuan Yan Zhengqin Xiong. Greenhouse gas emissions during the seedling stage of rice agriculture as affected by cultivar type and crop density. Biol Fertil Soils 2012 48:589–595.

Abstract

Methane (CH4) and nitrous oxide (N2O) emissions from a paddy nursery at the rice seedling stage were measured on a daily basis by using the conventional rice cultivar Nangeng 56 under both conventional (NG-C) and reduced (NG-R) sowing density and the hybrid rice Changyou 3 under both conventional (CY-C) and reduced (CY-R) sowing density. High N2O and CH4 emissions were observed
during the first and last 2 weeks respectively. Cumulative CH4 emissions were significantly  (P<0.001) affected by sowing density rather than by the rice cultivar. Cumulative CH4 emissions reached 68.2 kg C ha−1 in the CY-C treatment and 121.6 kg C ha−1 in the NG-C treatment which were significantly (P<0.001) higher than the emissions at reduced sowing densities (15.9 kg C ha−1 in the CY-R treatment and 20.9 kg C ha−1 in the NG-R treatment). Under the conventional sowing density cumulative CH4 emissions during the seedling stage were comparable to data of ricegrowing season. Both the rice cultivar and the sowing density significantly (P<0.05–0.01) affected cumulative N2O emissions. Relative to the CY cultivar the NG cultivar increased global warming potential (GWP) over a 100-year horizon by 62.1% and 70.7% under the reduced and conventional sowing densities respectively. The GWP of N2O and CH4 during the seedling stage was equivalent to the GWP of the entire ricegrowing season in this region indicating that the seedling stage is an important greenhouse gas emission source of rice agriculture.

XX Ye B Sun YL Yin. Variation of As concentration between soil types and rice genotypes and the selection of cultivars for reducing As in the diet. Chemosphere 2012 87: 384–389.

Abstract

Human exposure to toxic heavy metals via the food chain is of increasing concern. In the present study the effects of soil type and genotype on variation in arsenic (As) concentrations of different organs were investigated by using nine rice cultivars grown in two soils with two levels of As contamination. There were significant genotypic differences (P < 0.05) in As concentrations of all organs and As concentrations of polished grain were significantly affected by genotype and soil type. The As concentration in polished grain was higher in red paddy soil under As treatment with range from 0.24 to 1.03 mg kg1 and the As concentration of three cultivars exceeded the concentration of Chinese Food Hygiene Standard (0.7 mg kg1). The As concentrations in stems leaves and polished grain were all significantly and positively correlated. The As concentrations in polished grain were positively and significantly (P < 0.01) correlated with As root–grain translocation factor. The results indicated that As concentration in grain was partially governed by As uptake and the transfer of As from root to grain. The grain As concentration of the nine cultivars was significantly correlated between the two soil types at different levels of As contamination. Some genotypes such as japonica rice (e.g. Ning jing 1 and Nan jing 32) had consistently low grain As concentrations. The results suggest the possibility of breeding the As rice cultivars to produce grain for safe consumption from soils with slight and moderate levels of As.

    2011年12月27日-28日，实验室主任沈仁芳研究员主持的NSFC-JST重大国际合作研究项目“土壤酸化机制与酸性土壤生物修复研究”在南京举行了总结交流会。来自日本大学、南京土壤研究所、浙江大学和吉林大学等单位的中日双方共41人参加了此次会议。

    会上，中日双方代表分别从土壤、植物和微生物三个方面展示了三年来的研究内容与成果。三年来，本项目根据中日双方各自的优势在土壤、植物和微生物等领域开展了一对一的合作，取得了显著成效。南京土壤所的徐仁扣研究员课题组和日本大学的Ueda教授课题组等承担了土壤方面的研究内容，主要研究了氮肥施用及豆科植物和茶树根系释放质子等对土壤酸化的影响，植物物料和生物质碳对酸性土壤的修复和土壤中生物质碳的稳定性等，其中，生物质碳从制备到田间改良酸性土壤的效果再到其作用机理的系统和深入研究为酸性土壤的生物修复奠定了良好的基础。植物组由南京土壤所的沈仁芳研究员课题组、浙江大学的郑绍建教授课题组和日本大学的Hasegawa教授课题组等组成，筛选到了适合酸性土壤生长的耐铝水稻品种；成功克隆了与耐铝相关的饭豆柠檬酸转运子和胡枝子苹果酸转运子；提出了酸性土壤-植物系统中铝-氮相互作用的模式；通过转基因植物验证半胱氨酸合成酶（CSase）在植物耐酸胁迫中的作用及CSase基因超表达对多种代谢途径的影响等。南京土壤所的沈仁芳研究员课题组和日本大学的Sunairi教授课题组参加了微生物方面的研究，分离鉴定到一种能耐受200mM浓度铝的酵母菌，并深入探讨了其耐铝机理。

    最后，中日双方的负责人从研究工作进展、论文发表情况、学术活动和问题与展望等方面进行了总结，充分肯定了三年来中日双方一对一的学术交流和合作研究这种优势互补的合作形式，双方一致认为合作取得了如期成果，双方科学家增进了相互理解和友谊，并期待就双方共同感兴趣的问题进行进一步的实质性合作研究。

 会场

合影

 Li TL Bo LJ Yang F Zhang SQ Wu YH Yang LZ. Comparison of the removal of COD by a hybrid bioreactor at low and room temperature and the associated microbial characteristics. Bioresource Technology 2012 108:28-34. (IF 4.365 工程技术，一区）

摘要

To improve the efficiency of wastewater treatment and characterize the microorganism communities microorganisms were cultured and concentrated in hybrid bioreactors at a low temperature (similar to 4 degrees C low-temperature hybrid bioreactor LTHB) and room temperature (similar to 25 degrees C room-temperature hybrid bioreactor RTHB). The performance of the LTHB and RTHB in terms of COD removal efficiency dehydrogenase activity and functional diversity of microbial communities were evaluated. The results show COD removal efficiency increased gradually over time from 39.76% to 66.27% for LTHB and fluctuated between 81.85% and 94.78% for RTHB. The dehydrogenase activity and microbial activity in LTHB was higher than those in RTHB implying that microorganisms cultured at low temperature had higher activities and adaptabilities than those cultured at room temperature. This study suggests that hybrid bioreactors can treat wastewater at both low and room temperatures and provides valuable insight into the adaptation processes of the microorganisms during temperature changes. (c) 2012 Elsevier Ltd. All rights reserved.

    2011年12月18日，土壤与农业可持续发展国家重点实验室第三届第一次学术委员会会议在南京召开。傅伯杰院士等15位学术委员会委员和实验室全体研究员出席了本次会议。实验室学术顾问赵其国院士、朱兆良院士也受邀出席了会议。

    学术委员会主任周健民研究员主持了会议。实验室主任沈仁芳研究员为委员们颁发了聘书。实验室常务副主任张甘霖研究员针对实验室评估后的工作调整与进展作了汇报总结；实验室调整后设立的七个研究方向团队负责人分别围绕各研究方向的总体定位与近期目标、工作基础与拟解决的科学问题及预期成果作了详细汇报。会议还评审了2012年度室内优秀青年基金。

    与会学术委员会委员认真听取了会议并进行了审议。委员们普遍认为这次会议取得了很好的成效，并对实验室打破原有方向团队格局、重新凝练新方向的模式和思路给予了充分肯定，同时针对实验室调整后七个研究方向的进一步的凝练与提升、在更加注重基础、更加面向国家需求等方面需要改进和注意的问题等提出了非常重要的建议。本次会议对土壤与农业可持续发展国家重点实验室今后一个时期的发展将产生重要的促进和推动作用。